The uncoupling protein from brown-adipose-tissue mitochondria. Chymotrypsin-induced structural and functional modifications.


Mitoplasts prepared from brown adipose tissue mitochondria were treated with chymotrypsin and the fragments derived from the 32-kDa uncoupling protein identified by immunoblotting. Extensive proteolysis of the uncoupling protein occurred, the polypeptide pattern being affected by binding of the inhibitory nucleotide GDP. Chymotrypsin modifies the nucleotide… (More)